Embeded linux 之 mtd nand

应用层：(使用mtd ioctl)

　　0.获取mtd基本信息

　　　　struct mtd_info_user {
　　　　　　unsigned char type;　　//flash类型
　　　　　　unsigned int flags;　　  
　　　　　　unsigned int size; 　　  //分区大小
　　　　　　unsigned int erasesize; //块大小
　　　　　　unsigned int writesize;  //页数据大小
　　　　　　unsigned int oobsize;    //OOB大小
　　　　　　unsigned int ecctype;   //ECC类型
　　　　　　unsigned int eccsize;    //ECC大小
　　　　};

　　　　fd = open("/dev/mtd", O_RDWR);

　　　　ioctl(fd, MEMGETINFO, &mtd_info);

　　1.读页数据

　　　　

　　2.写页数据

　　　　unsigned char pagedate[2048] = {...};

　　　　write(fd, pagedate, mtd_info.writesize);

　　3.读OOB

　　　　struct mtd_oob_buf {
　　　　　　unsigned int start;
　　　　　　unsigned int length;
　　　　　　unsigned char *ptr;
　　　　};

　　　　unsigned char oobbuf2[64];

　　　　OOB_INFO.start = page_num * (2048);
　　　　OOB_INFO.ptr = oobbuf2;
　　　　ioctl(fd, MEMREADOOB, &OOB_INFO);

　　4.写OOB

　　　　unsigned char oobbuf[64] = {...};

　　　　OOB_INFO.start = page_num * (2048);
　　　　OOB_INFO.ptr = oobbuf;
　　　　ioctl(fd, MEMWRITEOOB, &OOB_INFO);

　　

  1 #include <stdlib.h>
  2 #include <unistd.h>
  3 #include <fcntl.h>
  4 #include <sys/stat.h>
  5 #include <sys/ioctl.h>
  6 #include <stdio.h>
  7 #include <string.h>
  8 #include <getopt.h>
  9 #include <errno.h>
 10 
 11 struct mtd_info_user {
 12     unsigned char    type;
 13     unsigned int    flags;
 14     unsigned int    size;             // Total size of the MTD
 15     unsigned int    erasesize;
 16     unsigned int    writesize;          // Size of OOB blocks (e.g. 512)
 17     unsigned int    oobsize;           // Amount of OOB data per block (e.g. 16)
 18     unsigned int    ecctype;
 19     unsigned int    eccsize;
 20 };
 21 struct mtd_oob_buf {
 22     unsigned int start;
 23     unsigned int length;
 24     unsigned char *ptr;
 25 };
 26 typedef long long    __kernel_loff_t;
 27 #define SLEEP_MILLI(milliseconds)        usleep(1000*(milliseconds))    /* sellp milliseconds */
 28 #define CORE_UPG_ONCE_SLP       (100)          /* 一次写入FLASH SLEEP时间 MS */
 29 
 30 #define MEMGETINFO                  _IOR('M' , 1 , struct mtd_info_user)
 31 #define MEMGETBADBLOCK                _IOW('M' , 11, __kernel_loff_t) 
 32 #define MEMWRITEOOB                    _IOWR('M', 3 , struct mtd_oob_buf) 
 33 #define MEMREADOOB                    _IOWR('M', 4 , struct mtd_oob_buf)
 34 
 35 static unsigned int next_good_eraseblock(int fd, struct mtd_info_user *meminfo,
 36         unsigned block_offset)
 37 {
 38     loff_t offs;
 39     
 40     while (1) 
 41     {
 42         if (block_offset >= meminfo->size) 
 43         {
 44             printf("next_good_eraseblock:not enough space in MTD device
");
 45             return block_offset; 
 46         }
 47         
 48         offs = block_offset;
 49         if (ioctl(fd, MEMGETBADBLOCK, &offs) == 0) 
 50         {
 51             return block_offset;
 52         }
 53         
 54         printf("Skipping bad block at 0x%08x
", block_offset);
 55         block_offset += meminfo->erasesize;
 56     }
 57 }
 58 int main(void)
 59 {
 60     int fd     = -1;
 61     int ret = 0;
 62     int i = 0,k = 0;
 63     
 64     int writesize             = 0;
 65     unsigned int erasesize     = 0;
 66     unsigned int blockSize     = 0;
 67     int wrt_cnt                = 0;
 68     int wrt_left            = 0;
 69     unsigned int size         = 0;
 70     unsigned int offset     = 0;
 71     
 72     struct mtd_info_user mtd_info;    //MTD信息
 73     struct mtd_oob_buf OOB_INFO ;    //OOB操作时用
 74     unsigned char oobbuf2[64];        //读取OOB时用的缓存
 75     //一页(2048Byte)有效的yaffs2信息头
 76     unsigned char pagedate[2048] = {
 77         0x59,0x46,0x53,0x53,0x21,0x56,0x31,0x30,0x10,0x06,0x00,0x00,0x02,0x06,0x23,0x07,//Y F S S ! V 1 0 DLE ACK NUL NUL STX ACK # BEL
 78         0x00,0x08,0x00,0x00,0x02,0x00,0x00,0x00,0x7e,0x00,0x0a,0x79,0x61,0x66,0x66,0x73,//NUL BS NUL NUL STX NUL NUL NUL ~ NUL LF y a f f s
 79         0x32,0x20,0x66,0x69,0x6c,0x65,0x20,0x73,0x79,0x73,0x74,0x65,0x6d,0x3a,0x20,0x32,//2 (space) f i l e (space) s y s t e m : (space) 2  
 80         0x4b,0x20,0x34,0x62,0x69,0x74,0x20,0x0a,0x6d,0x6b,0x79,0x61,0x66,0x66,0x73,0x32,//K (space) 4 b i t (space) . m j y a f f s 2 
 81         0x69,0x6d,0x61,0x67,0x65,0x20,0x76,0x65,0x72,0x73,0x69,0x6f,0x6e,0x3a,0x20,0x4c,//i m a g e (space) v e r s i o n : (space) L
 82         0x69,0x6e,0x75,0x78,0x2d,0x32,0x2e,0x36,0x2e,0x33,0x35,0x20,0x4e,0x61,0x6e,0x64,//i n u x - 2 . 6 . 3 5 (space) N a n d 
 83         0x20,0x43,0x6f,0x6e,0x74,0x72,0x6f,0x6c,0x6c,0x65,0x72,0x20,0x56,0x36,0x31,0x30,//(space) C o n t r o l l e r (space) V 6 1 0
 84         0x2c,0x20,0x62,0x75,0x69,0x6c,0x64,0x20,0x74,0x69,0x6d,0x65,0x3a,0x20,0x57,0x65,//, (space) b u i l d (space) t i m e : (space) W e
 85         0x64,0x20,0x4d,0x61,0x79,0x20,0x32,0x34,0x20,0x31,0x37,0x3a,0x32,0x30,0x3a,0x33,//d (space) M a y (space) 2 4 (space) 1 7 : 2 0 : 3
 86         0x34,0x20,0x32,0x30,0x31,0x37,0x0a,0x2e,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,//4 (space) 2 0 1 7 NUL NUL NUL NUL NUL NUL NUL NUL NUL NUL
 87         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 88         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 89         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 90         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 91         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 92         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 93         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 94         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 95         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 96         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 97         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 98         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
 99         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
100         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
101         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
102         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
103         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
104         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
105         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
106         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
107         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
108         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
109         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
110         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
111         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
112         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
113         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
114         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
115         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
116         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
117         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
118         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
119         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
120         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
121         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
122         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
123         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
124         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
125         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
126         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
127         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
128         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
129         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
130         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
131         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
132         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
133         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
134         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
135         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
136         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
137         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
138         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
139         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
140         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
141         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
142         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
143         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
144         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
145         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
146         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
147         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
148         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
149         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
150         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
151         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
152         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
153         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
154         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
155         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
156         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
157         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
158         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
159         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
160         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
161         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
162         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
163         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
164         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
165         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
166         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
167         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
168         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
169         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
170         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
171         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
172         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
173         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
174         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
175         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
176         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
177         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
178         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
179         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
180         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
181         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
182         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
183         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
184         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
185         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
186         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
187         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
188         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
189         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
190         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
191         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
192         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
193         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
194         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
195         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
196         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
197         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
198         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
199         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
200         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
201         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
202         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
203         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
204         0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
205         };
206     //一页(2048Byte)对应的有效的yaffs2 ecc值
207     unsigned char oobbuf[64] = {
208         0xff,0xff,0x00,0x10,0x00,0x00,0x01,0x01,
209         0x00,0x00,0x00,0x04,0x00,0x00,0x99,0x00,
210         0x00,0x00,0x3c,0x00,0x00,0x00,0x09,0x00,
211         0x00,0x00,0x09,0x00,0x00,0x00,0xff,0xff,
212         0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
213         0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
214         0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
215         0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
216     };
217     //1.打开设备    
218     fd = open("/dev/mtd4", O_RDWR);
219     if (fd < 0) 
220     {
221         printf("nand_write:open
");
222         ret = -1;
223         return ret;
224     }
225     //2.获取存储信息
226     if (ioctl(fd, MEMGETINFO, &mtd_info) < 0) 
227     {
228         printf("nand_write:MEMGETINFO
");
229         ret = -1;
230         return ret;
231     }
232     offset = 0 & ~(mtd_info.erasesize - 1);//数据在mtd中的偏移
233     writesize = mtd_info.writesize;//页大小
234     blockSize = mtd_info.erasesize;//块大小    
235     size = mtd_info.size;//16*1024*1024 实例大小为16M
236     
237     erasesize = mtd_info.erasesize;//擦除大小
238     wrt_cnt  = size / writesize;//分区页数
239     wrt_left = size % writesize;//分区最后一页字节数
240     memset(oobbuf, 0xff, sizeof(oobbuf));//写OOB时缓存
241     memset(oobbuf2, 0xff, sizeof(oobbuf2));//读OOB时缓存
242     OOB_INFO.start = 0;//OOB页起始地址
243     OOB_INFO.length = mtd_info.oobsize;//OOB大小
244     /*
245      * 读所有页OOB
246      */
247     for (i = 0; i < wrt_cnt; i++)//页数
248     {
249         if (!(offset % blockSize))
250         {
251             offset = next_good_eraseblock(fd, &mtd_info, offset);    
252             if (offset >= mtd_info.size) 
253             {
254                 printf("nand_write:MTD is full
");
255                 ret = -1;
256                 return ret;
257             }
258         }  
259         OOB_INFO.start    = offset;
260         OOB_INFO.ptr    = oobbuf;
261 
262         ioctl(fd, MEMREADOOB, &OOB_INFO);
263         for(k = 0; k < mtd_info.oobsize; k++)
264             printf("OOB_INFO[%d] = %#x
", k,*(OOB_INFO.ptr+k));
265         offset += writesize;
266         if (0 == i % 25)             // 每写100KB数据后暂停100ms，防止升级线程占用太多CPU 资源    
267         {
268                // 每写100KB数据后暂停100ms，防止升级线程占用太多CPU 资源
269             SLEEP_MILLI(CORE_UPG_ONCE_SLP);
270         }
271     }
272     if (wrt_left > 0) 
273     {
274         if (!(offset % blockSize))
275         {
276             offset = next_good_eraseblock(fd, &mtd_info, offset);    
277             if (offset >= mtd_info.size) 
278             {
279                 printf("nand_write:MTD is full
");
280                 ret = -1;
281                 return ret;
282             }
283         } 
284         OOB_INFO.start    = offset;
285         OOB_INFO.ptr    = oobbuf;
286         ioctl(fd, MEMREADOOB, &OOB_INFO);
287         for(k = 0; k < mtd_info.oobsize; k++)
288             printf("OOB_INFO[%d] = %#x
", k,*(OOB_INFO.ptr+k));
289         offset += writesize;
290     }
291     
292     write(fd, pagedate, mtd_info.writesize);
293     
294     /*
295      * 写指定页OOB
296      */
297     offset = 0 * (2048);
298     if (!(offset % blockSize))
299     {
300         offset = next_good_eraseblock(fd, &mtd_info, offset);    
301         if (offset >= mtd_info.size) 
302         {
303             printf("nand_write:MTD is full
");
304             ret = -1;
305             return ret;
306         }
307     } 
308     OOB_INFO.start    = offset;
309     OOB_INFO.ptr    = oobbuf;    
310     ioctl(fd, MEMWRITEOOB, &OOB_INFO);
311 
312     /*
313      * 读指定页OOB
314      */    
315     OOB_INFO.start    = 0 * (2048);
316     OOB_INFO.ptr    = oobbuf2;
317     ioctl(fd, MEMREADOOB, &OOB_INFO);
318     for(k = 0; k < mtd_info.oobsize; k++)
319         printf("OOB_INFO[%d] = %#x
", k,*(OOB_INFO.ptr+k));
320     return 0;
321 }
mtd demo

　　　　

【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/pokerface/p/6927347.html